/// <summary>
 /// Create play list window.
 /// </summary>
 private void CreateListWindow()
 {
     if (this.listWindow == null)
     {
         this.listWindow = new ListWindow()
         {
             LibraryManager = this
         };
         this.listWindow.Owner = this.GetWindowHostControl();
         this.listWindow.Show();
         this.listWindow.Closed += new EventHandler(listWindow_Closed);
     }
     else
     {
         this.listWindow.Focus();
     }
 }
 /// <summary>
 /// Deselect checboxes and context menu item.
 /// </summary>
 void listWindow_Closed(object sender, EventArgs e)
 {
     this.IsPlayListCheckBoxChecked = false;
     this.listWindow = null;
 }